N deficiency halfway through flowering -- too late, or bump up N?

Sick Plants & Problems
#1

I’m about halfway done flowering a Tangilope (over here if you want to look), and it had been shedding inner/lower leaves for a couple of weeks – no big deal, these leaves weren’t getting any light anyway. Looks like classic nitrogen deficiency, don’t really have any question about that.

However, giving it a peek this morning, the yellowing has started on quite a few ‘useful’ fan leaves, and I’ve still got 30-or-so days of flowering to go.

Is it too late to give a little boost of nitrogen? I’m feeding with a GO box, and was planning to give a 50/50 split of “Bloom” and “Grow” for the next couple waterings to try and curb the leaf yellowing/leaf loss, but figured I’d ask for some advice before confusing a flowering plant with extra nitrogen.

Papaya, Tangilope, and Wreckage flowering
#2

As usual, take my advice with a grain of salt, i am mearly a mortal who is fallible (-; ok, i have had no issues putting a little n in late flower on plants i felt needed it. Not much, but a bit. I am not one who likes to “starve” a plant.

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#3

I would not hesitate to give them additional N at this point.
I like to keep as many leaves as green as I can all through flowering.
Good luck😎

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#4

I agree with Mr. Moog here. I love to fade my plants, so often with hold a little nitrogen mid to late flower. A little nitrogen won’t hurt. If you turn them dark green after they start to yellow then you could retard bud development and restart leaf development. All you want to do is slow the yellowing. The plant wants to live long enough to make as much seed as possible not grow the biggest buds as possible. I hope this helps.

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#5

Yes, I’m not afraid to boost little bit of Nitrogen (or mix partly grow formula in addition to bloom formula) when in halfway leaves seem to yellow …

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#6

i always feed kelp in flower. fuck swtching it upXD at that time. i would give it a 1/4 to 1/2 dose of veg just to make sure you dont get a toxicity.

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#7

Universal consensus wins :grinning: I’ll give her a mix of veg+bloom when I feed her tomorrow, and post and update at day 40 in my pics thread. Thanks for the replies, all!

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#8

Its a matter of “feel”, I usually try to add only enough to have them prosperous during whole bloom but to see leaves yellowing (or at least lighten up a bit) last week of flushing (as a sign all nutes have been processed from the solution)… Just my two cents…

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#9

Hate to ask, are you sure its N problems?. Chlorosis with veins staying green means it might not be a nitrogen problem.

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#10

Always start with the basics, check PH, over/underwatering, frequency. Temps, RH. Soil condition, drainage… and yes pests…

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#11

No, I just strongly suspect :slight_smile: pH is good: I adjust to 6.3-6.7 going in, run-off seems to be about the same. Water every 3-4 days, about 2-2.5L at a time, waiting until the top 2ish inches are dry and the pots feel a little “light.” Temps have been a little chillier than usual for the past week, 70f day/55f night, though the previous couple weeks were 73/59. RH is between 35% and 55%, but usually hovers towards the middle. Soil seems a-ok, drainage is good, and I make sure to remove any run-off. I have fungus gnats in one of my houseplants (under control now), but flower box is far away and its air intake is filtered.

The girls are awake now, so some pics might help to confirm/deny. Yeah, they probably have a bit of P/K deficiency, too, but I upped the bloom nutrients a bit and that seems to have helped.

leaf1.jpg1200×1281 376 KB

leaf2.jpg1200×1499 366 KB

The top is much prettier:

happy.jpg1200×1455 426 KB

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#12

Well for starters, you have alot of temp differential, for example I see a 15 degree temp differential. I try to keep temps tighter than that. You have 15 degree DIF, thats alot, I work with a 7 degree DIF at one of the medical grows I’m working.

Observation
Nighttime temp is out of spec That can cause phosporous problems.
I see purple/red stems could be N,P,
Yellowing of veins
Lower foilage “draw” as I call it could be from shading but looking at other things. It looks deficient, the leaves have chlorosis, but do not have green veins.
Tip dieback and claw.
Top foilage looks ok.

How you got there…
N is needed in first weeks of stretch, now its showing low N.
P is easily blocked, or locked up, or used up. PK is immobile in soil.
Lower shaded foilage can fade, the rest of the plant can draw from these leaves, looking like fade. I even see it in hydro. Fan leaf drop does happen even in perfectly fed plants.
Increased need of P during flower.
Nighttime temp is out of spec That can cause phosporous problems.

Possible fix:
-Nighttime temps with less DIF and temps closer to normal 65+ Verify soil temps with probe or non contact IR thermometer. Get into proper range.

-Foliar feed, use a very dilute solution of macros’ NPK and I lean towards nitrate based stuff, mainly for solubility.
And you can use a surfactant with it, spray the bottoms of the leafs, prior to lights out or before lights on. Less of a cuticle to worry about penetrating and the stomata are open. you can use soaps for a surfactant, but typical dish soap isn’t really designed for wetting. Spreader, sticker wetting agents are relatively cheap. Be careful of burn, you could try a typical off the shelf solution, or some type of organic formulation, be careful of what you use if organic, fungal or PM outbreak could occur due to lower temps at night. Avoid application to budsites,

-Inoculant using microbes, powdered molasses and humics and fulvics to possibly unlock PK. I hate to plug any product, but “Recharge” works fairly well (Realgrowers.com) Or a light topdressing of EWC and compost. Topdressing is a very easy way to help soil biology and chemistry and tilth.

-Fish based or protein based fertilizers or products with high nitrogen to help bump the chemistry in the right direction, I am partial to fish… They have alot of microbe activity, and you can find balanced fish fertilizers.

Test soil if possible.

Just some thoughts… No warranty expressed or implied.

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#13

Wow, im have a much larger temp spread than that my last grow without seeing anything like that, a little stretchier, but nothing like that. 45 at night 78 during the day. I know outside here, you get huge temp diffs also.

#14

And this is why I’m glad that Overgrow is back :smile: thank you for the thorough reply, that’s some top-notch weed nerdery.

I’ll try to get my night temperatures up a bit, though it looks like nature is going to be helping with that this week, anyway. I have a large seed starting mat which would probably knock up the temperature of the tent a few degrees and help keep the Tangilope’s feet warm in the meantime.

The… density… of the plant might make foliar feeding difficult, but a topdressing of EWC sounds like a good idea, and I’ll throw some humics in when I feed. Not to get too off topic, but does powdered molasses have a different effect than liquid? I was planning to add a dash of blackstrap molasses soon, anyway, and my local grow shop doesn’t carry powdered.

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#15

As long as its unsulphured molasses, I dont really know if there is a difference, I’ve never done a side by side with powder and liquid looking at microbes under the microscope.

I cant comment if the concentration is going to be different. for powder or liquid either… Its low, mebby 1 tbsp a gallon, for either… I cant really say.

#16

Controlling DIF seems to control stretch too. Not too big a deal if you are outdoors.

#17

That im well aware of…lol i now heat at night. But stretch is the only thing i have noticed.

#18

Your ph is out of wack. Flowering nutes will have enpugh n to keep em green till the end. If your leaves r yellowing and falling off its your ph most likely. If those leaves were not getting any light anyway they should have been pruned and lollypoped

The leaves that fall r they crispy or soft?

Get your ph on point. Try some humics and kelp.

Good luck!

#19

@Sourog this thread is 9months old. Welcome to overgrow. Please post a introduction so people can get to know you. :+1:

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